1. Technical Field of the Invention
The present invention relates to mobile originating short message services, and more particularly, to transmission of the R.sub.-- DATA message on an air interface.
2. Description of Related Art
The IS-136 standard defines the air interface between a mobile station and a base station. The IS-136 standard supports mobile originating short message services (MO SMS), enabling a mobile station to originate and transmit SMS messages. Within the IS-136 protocol, the R.sub.-- DATA LENGTH parameter defines the maximum length of the R.sub.-- DATA uplink message. The IS-136 standard provides no guidelines for determining how the R.sub.-- DATA LENGTH parameter should be set. Nor does the IS-136 standard provide any access priority scheme between SMS messages or voice/data/fax calls. Thus, once a random access channel (RACH) sub-channel is seized for any kind of access, the channel is no longer available for an additional access. Once all sub-channels are seized, other mobile stations requiring access to the RACH will be unsuccessful.
This presents a problem to mobile system operators who desire voice/data/fax accesses to comprise a larger share of the channel traffic than SMS message traffic, since these types of accesses provide more revenue due to their increased access length times. Thus, setting the R.sub.-- DATA LENGTH parameter in a static manner can lead to a loss of revenue during low traffic load times due to system capacity being under used by MO SMS users. Similarly, during high traffic load periods, revenues are lost from voice/data/fax accesses due to RACH congestion with MO SMS users.